#define  _CRT_SECURE_NO_WARNINGS 1


#include <stdio.h>
#include <string.h>

int My_strcmp(const char* s1, const char* s2)
{
	while (*s1 == *s2)
	{
		if (*s1 == '\0')
		{
			return 0;
		}
		s1++;
		s2++;
	}
	return *s1 - *s2;

}

int main()
{
	char s1[] = "ab";
	char s2[] = "abcd";
	int r = strcmp(s1, s2);
	int j = My_strcmp(s1, s2);
	printf("%d\n%d", r, j);
	return 0;
}